1  /* SPDX-License-Identifier: GPL-2.0-only */
  2  
  3  #ifndef _CBMEM_H_
  4  #define _CBMEM_H_
  5  
  6  #include <commonlib/bsd/cbmem_id.h> /* IWYU pragma: export */
  7  #include <stddef.h>
  8  #include <stdint.h>
  9  #include <boot/coreboot_tables.h>
 10  
 11  #define CBMEM_FSP_HOB_PTR	0x614
 12  
 13  struct cbmem_entry;
 14  
 15  /*
 16   * The dynamic cbmem infrastructure allows for growing cbmem dynamically as
 17   * things are added. It requires an external function, cbmem_top(), to be
 18   * implemented by the board or chipset to define the upper address where
 19   * cbmem lives. This address is required to be a 32-bit address. Additionally,
 20   * the address needs to be consistent in both romstage and ramstage.  The
 21   * dynamic cbmem infrastructure allocates new regions below the last allocated
 22   * region. Regions are defined by a cbmem_entry struct that is opaque. Regions
 23   * may be removed, but the last one added is the only that can be removed.
 24   */
 25  
 26  #define DYN_CBMEM_ALIGN_SIZE (4096)
 27  #define CBMEM_ROOT_SIZE      DYN_CBMEM_ALIGN_SIZE
 28  
 29  /* The root region is at least DYN_CBMEM_ALIGN_SIZE . */
 30  #define CBMEM_ROOT_MIN_SIZE DYN_CBMEM_ALIGN_SIZE
 31  #define CBMEM_LG_ALIGN CBMEM_ROOT_MIN_SIZE
 32  
 33  /* Small allocation parameters. */
 34  #define CBMEM_SM_ROOT_SIZE 1024
 35  #define CBMEM_SM_ALIGN 32
 36  
 37  /* Determine the size for CBMEM root and the small allocations */
 38  static inline size_t cbmem_overhead_size(void)
 39  {
 40  	return 2 * CBMEM_ROOT_MIN_SIZE;
 41  }
 42  
 43  /* By default cbmem is attempted to be recovered. Returns 0 if cbmem was
 44   * recovered or 1 if cbmem had to be reinitialized. */
 45  int cbmem_initialize(void);
 46  int cbmem_initialize_id_size(u32 id, u64 size);
 47  
 48  /* Initialize cbmem to be empty. */
 49  void cbmem_initialize_empty(void);
 50  void cbmem_initialize_empty_id_size(u32 id, u64 size);
 51  
 52  /* Return the top address for dynamic cbmem. The address returned needs to
 53   * be consistent across romstage and ramstage, and it is required to be
 54   * below 4GiB for 32bit coreboot builds. On 64bit coreboot builds there's no
 55   * upper limit. This should not be called before memory is initialized.
 56   */
 57  /* The assumption is made that the result of cbmem_top_romstage fits in the size
 58     of uintptr_t in the ramstage. */
 59  extern uintptr_t _cbmem_top_ptr;
 60  uintptr_t cbmem_top(void);
 61  /* With CONFIG_RAMSTAGE_CBMEM_TOP_ARG set, the result of cbmem_top is passed via
 62   * calling arguments to the next stage and saved in the global _cbmem_top_ptr
 63   * global variable. Only a romstage callback needs to be implemented by the
 64   * platform. It is up to the stages after romstage to save the calling argument
 65   * in the _cbmem_top_ptr symbol. Without CONFIG_RAMSTAGE_CBMEM_TOP_ARG the same
 66   * implementation as used in romstage will be used.
 67   */
 68  uintptr_t cbmem_top_chipset(void);
 69  
 70  /* Add a cbmem entry of a given size and id. These return NULL on failure. The
 71   * add function performs a find first and do not check against the original
 72   * size. */
 73  const struct cbmem_entry *cbmem_entry_add(u32 id, u64 size);
 74  
 75  /* Find a cbmem entry of a given id. These return NULL on failure. */
 76  const struct cbmem_entry *cbmem_entry_find(u32 id);
 77  
 78  /* Remove a region defined by a cbmem_entry. Returns 0 on success, < 0 on
 79   * error. Note: A cbmem_entry cannot be removed unless it was the last one
 80   * added. */
 81  int cbmem_entry_remove(const struct cbmem_entry *entry);
 82  
 83  /* cbmem_entry accessors to get pointer and size of a cbmem_entry. */
 84  void *cbmem_entry_start(const struct cbmem_entry *entry);
 85  u64 cbmem_entry_size(const struct cbmem_entry *entry);
 86  
 87  /* Returns 0 if old cbmem was recovered. Recovery is only attempted if
 88   * s3resume is non-zero. */
 89  int cbmem_recovery(int s3resume);
 90  /* Add a cbmem entry of a given size and id. These return NULL on failure. The
 91   * add function performs a find first and do not check against the original
 92   * size. */
 93  void *cbmem_add(u32 id, u64 size);
 94  /* Find a cbmem entry of a given id. These return NULL on failure. */
 95  void *cbmem_find(u32 id);
 96  
 97  /* Indicate to each hook if cbmem is being recovered or not. */
 98  typedef void (* const cbmem_init_hook_t)(int is_recovery);
 99  void cbmem_run_init_hooks(int is_recovery);
100  
101  /* Ramstage only functions. */
102  /* Add the cbmem memory used to the memory map at boot. */
103  void cbmem_add_bootmem(void);
104  /* Return the cbmem memory used */
105  int cbmem_get_region(void **baseptr, size_t *size);
106  void cbmem_list(void);
107  void cbmem_add_records_to_cbtable(struct lb_header *header);
108  
109  #define _CBMEM_INIT_HOOK_UNUSED(init_fn_) __attribute__((unused)) \
110  	static cbmem_init_hook_t init_fn_ ## _unused_ = init_fn_
111  
112  #define _CBMEM_INIT_HOOK(init_fn_) \
113  	static cbmem_init_hook_t init_fn_ ## _ptr_ __attribute__((used, \
114  	section(".rodata.cbmem_init_hooks"))) = init_fn_
115  
116  /* Early hooks get executed before other hooks. Use sparingly for hooks that create
117     CBMEM regions which need to remain in a constant location across boot modes. */
118  #define _CBMEM_INIT_HOOK_EARLY(init_fn_) \
119  	static cbmem_init_hook_t init_fn_ ## _ptr_ __attribute__((used, \
120  	section(".rodata.cbmem_init_hooks_early"))) = init_fn_
121  
122  /* Use CBMEM_CREATION_HOOK for code that needs to be run when cbmem is initialized
123     for the first time. */
124  #if ENV_CREATES_CBMEM
125  #define CBMEM_CREATION_HOOK(x)		_CBMEM_INIT_HOOK(x)
126  #else
127  #define CBMEM_CREATION_HOOK(x)		_CBMEM_INIT_HOOK_UNUSED(x)
128  #endif
129  
130  /* Use CBMEM_READY_HOOK for code that needs to run in all stages that have cbmem. */
131  #if ENV_HAS_CBMEM
132  #define CBMEM_READY_HOOK(x)		_CBMEM_INIT_HOOK(x)
133  #define CBMEM_READY_HOOK_EARLY(x)	_CBMEM_INIT_HOOK_EARLY(x)
134  #else
135  #define CBMEM_READY_HOOK(x)		_CBMEM_INIT_HOOK_UNUSED(x)
136  #define CBMEM_READY_HOOK_EARLY(x)	_CBMEM_INIT_HOOK_UNUSED(x)
137  #endif
138  
139  /* Returns 1 after running cbmem init hooks, 0 otherwise. */
140  static inline int cbmem_online(void)
141  {
142  	extern int cbmem_initialized;
143  
144  	if (!ENV_HAS_CBMEM)
145  		return 0;
146  
147  	return cbmem_initialized;
148  }
149  
150  #endif /* _CBMEM_H_ */